The 22-year-old singer and actress looked super cool in a edgy black and white mini-dress as she stepped out for the event.
Also stepping out for the event was Niall Horan – who looked handsome in a navy, plaid suit on the red carpet.
If you forgot, Niall and Hailee dated for a few months last year before splitting up in December.
Check out the full list of winners at the Grammys here.
FYI: Hailee is wearing a Giambattista Valli Haute Couture dress and Jimmy Choo heels.